CHICAGO—Early one morning last spring, shortly after moving into her apartment, Kristen Caston was jolted awake by a thud so powerful it nearly knocked the artwork from her walls.

“I thought it was an earthquake,” she said. “It literally sounded like somebody was taking a huge drill to the floor.”

Alas, it was her neighbor: a CrossFit gym, where men and women routinely hoist barbells weighing hundreds of pounds above their heads, then let them crash to the floor.

CrossFit, a fitness regimen that grew out of a suburban garage in California nearly two decades ago, is now an urban fixture with more than 6,000 locations across the U.S., and many other clubs that have adopted the style. Gyms squeeze into apartment and office buildings, catering to millennials looking to get fit with Olympic movements like the “snatch” and the “clean and jerk.”

Barbell

But appeasing neighbors is proving to be a heavy lift. Residents have formed a not-in-my-backyard counter movement, complaining of vibrating condos, noise from loud music and the need to dodge herds of sprinting runners on city sidewalks. (Running is often a part of CrossFit “wods,” or workouts of the day.)

Over the past year, CrossFit gyms and their neighbors have clashed in courts in New York, Los Angeles, San Francisco and Chicago. In January, a New York City judge ordered the eviction of a CrossFit gym from a Chelsea condo building, where owners of the multimillion-dollar units above complained of the vibrations from dropped weights.

The city council in Austin, Texas, recently passed a measure to crack down on noise from CrossFit gyms after residents mobilized against a gym in their neighborhood.

And in Manhattan Beach, Calif., a married couple spent 20 days in jail this year after they violated a restraining order filed by the owner of the gym next to their beachfront home. The dispute began after the couple awoke at 6 a.m. to the vibrations of a gym client repeatedly slamming a medicine ball—a common feature of CrossFit workouts— on the ground. Cursing bouts ensued, with the owner of the gym—which isn’t a CrossFit affiliate but used many of the same exercises—accusing the couple of at one point banging a sledgehammer against the side of the building and harassing clients.

Russell Berger,
a CrossFit trainer and a spokesman for CrossFit Inc. in Santa Cruz, Calif., said individual affiliates operate largely autonomously. Many target industrial areas and are careful to avoid moving into residential buildings, and have invested in padding to muffle noise, he said. But he acknowledged that CrossFit’s unique workout style represents a cultural shift from typical gyms.

In a typical gym “it’s awkward and it’s quiet,” said Mr. Berger, who recalls being kicked out of one after making too much noise with the weights. “Everybody’s got their own headphones in and looking in the mirror, and it’s this weird posturing—sort of a bizarre environment where not a lot of work is actually getting done.”

CrossFit’s main weight movements are the “snatch” and the “clean and jerk.” Each exercise involves the athlete lifting a barbell from the ground and hoisting it over his or her head. Veterans can lift 200 to 300 pounds, and many drop the barbell from midair after the lift, rather than crashing it on their shoulders or allowing other risky maneuvers.

“If you go in there with the expectation that everything’s going to be quiet, you’re in the wrong place,” Mr. Berger said. “The process of training in a way that gets results requires some noise and some sweat.”

Kristen Caston outside her former apartment in Chicago, which shares a wall with a CrossFit gym. She moved to find peace from the crashing weights and pounding music.
Photo:
Joshua Mitchell/The Wall Street Journal

But some businesses say operating next to a CrossFit is akin to living next to a perpetual construction site. “There are hundreds of bangs a day,” said Jay Baumgardner, owner of NRG Recording Studios, in North Hollywood, Calif. “It’s a really, really low frequency. It’s almost like an earthquake or an explosion.”

Mr. Baumgardner’s clients have included Kanye West and Linkin Park, and his studio has been around since the 1980s. Last year, a CrossFit gym moved next door and, he said, it started to disrupt his recordings. He is now trying to get the gym evicted in an ongoing court case.

The owners of the gym, CrossFit Synapse, say they chose the location because it is a stand-alone building in an industrial area. Their building is several feet from Mr. Baumgardner’s and doesn’t share a wall. “They require very pristine sound conditions,” said Synapse co-owner Jimmy Lujan. “An average person wouldn’t find the noise a nuisance.”

Mr. Baumgardner said: “The crazy thing is, we walk out and hear the music that’s been recorded at the studio coming from the gym—songs that I’ve produced.”

Many residents find that regulations in their cities don’t address noise from CrossFit.

In Chicago, a city ordinance forbids loud noise overnight, but neighbors say they have been told it doesn’t preclude CrossFit gyms from operating during the day. Residents of a 12-story, 165-unit building in the city’s north side have called the police numerous times to report noise at River North CrossFit, located on the first floor of their building, directly behind the lobby.

On a recent afternoon, more than a dozen athletes practiced the “snatch” with a coach. The rapper Chingy’s “Holidae In” blared in the background as athletes hoisted barbells, some holding 95 pounds, then dropped them, causing a loud thwack.

John Lee, one of three co-owners, says the gym has taken steps to alleviate noise, including laying down padding for heavy lifts and moving workouts away from the walls to avoid vibrations.

“We’re trying to be good neighbors,” Mr. Lee said. He pointed out that a two-floor garage separates the gym from the condo units in the building.

A couple of miles away, Ms. Caston, the Chicago resident, moved into a boutique apartment building last year that shared a wall with a CrossFit gym. The 31-year-old graphic designer said she would wake up repeatedly at 5:30 a.m. to vibrations.

One day, she came home and found a shattered wine glass on the floor. “You know like ‘Jurassic Park,’ and they’re looking at the water glass and it was like ripples because the dinosaurs are walking around you? It was like that,” she said.

Even when she went outside, she couldn’t find peace. “I would go out back and read a book,” she said. “It was Nickelback playing and guys screaming. It was my worst nightmare.” She recalled having a cookout with friends at the same time the CrossFit gym had its own cookout. There were awkward stares between the camps.

She called the police several times, and one officer showed up once and told her there was nothing they could do because the gym wasn’t in violation of the city’s regulations. The owner of the gym declined to comment.

Ms. Caston said her landlord, who works out at the CrossFit gym, allowed her out of her lease. She moved directly across the street into an apartment with much more expensive rent. But she says she now gets a good night’s sleep.